diff --git a/dhall-lsp-server.cabal b/dhall-lsp-server.cabal
--- a/dhall-lsp-server.cabal
+++ b/dhall-lsp-server.cabal
@@ -1,5 +1,5 @@
 name:           dhall-lsp-server
-Version:        1.1.0
+Version:        1.1.1
 cabal-version:  1.12
 synopsis:       Language Server Protocol (LSP) server for Dhall
 homepage:       https://github.com/dhall-lang/dhall-haskell/tree/master/dhall-lsp-server#readme
@@ -42,7 +42,7 @@
       src
   default-extensions: RecordWildCards OverloadedStrings
   build-depends:
-      aeson                >= 1.3.1.1  && < 1.6
+      aeson                >= 1.3.1.1  && < 2.1
     , aeson-pretty         >= 0.8.7    && < 0.9
     , base                 >= 4.11     && < 5
     , bytestring           >= 0.10.8.2 && < 0.12
@@ -103,7 +103,7 @@
     Main-Is: Main.hs
     GHC-Options: -Wall
     Build-Depends:
-        base                                   ,
+        base                                    ,
         lsp-types         >= 1.2.0.0  && < 1.5  ,
         hspec             >= 2.7      && < 2.10 ,
         lsp-test          >= 0.13.0.0 && < 0.15 ,
diff --git a/src/Dhall/LSP/Handlers.hs b/src/Dhall/LSP/Handlers.hs
--- a/src/Dhall/LSP/Handlers.hs
+++ b/src/Dhall/LSP/Handlers.hs
@@ -3,6 +3,7 @@
 {-# LANGUAGE DataKinds      #-}
 {-# LANGUAGE NamedFieldPuns #-}
 {-# LANGUAGE MultiWayIf     #-}
+{-# LANGUAGE ViewPatterns   #-}
 
 module Dhall.LSP.Handlers where
 
@@ -125,14 +126,16 @@
 -- helper
 rangeToJSON :: Range -> LSP.Types.Range
 rangeToJSON (Range (x1,y1) (x2,y2)) =
-    LSP.Types.Range (Position x1 y1) (Position x2 y2)
+    LSP.Types.Range
+      (Position (fromIntegral x1) (fromIntegral y1))
+      (Position (fromIntegral x2) (fromIntegral y2))
 
 hoverHandler :: Handlers HandlerM
 hoverHandler =
     LSP.requestHandler STextDocumentHover \request respond -> do
         let uri_ = request^.params.textDocument.uri
 
-        let Position{ _line, _character } = request^.params.position
+        let Position{ _line = fromIntegral -> _line, _character = fromIntegral -> _character } = request^.params.position
 
         errorMap <- use errors
 
@@ -301,7 +304,7 @@
 
         ServerConfig{..} <- liftLSP LSP.getConfig
 
-        let numLines = Text.length txt
+        let numLines = fromIntegral (Text.length txt)
         let _newText= formatExprWithHeader chosenCharacterSet expr header
         let _range = LSP.Types.Range (Position 0 0) (Position numLines 0)
 
@@ -353,7 +356,7 @@
 
   ServerConfig{..} <- liftLSP LSP.getConfig
 
-  let numLines = Text.length txt
+  let numLines = fromIntegral (Text.length txt)
 
   let _newText = formatExprWithHeader chosenCharacterSet (lint expr) header
 
@@ -380,8 +383,8 @@
 executeAnnotateLet request = do
   args <- getCommandArguments request :: HandlerM TextDocumentPositionParams
   let uri_ = args ^. textDocument . uri
-      line_ = args ^. position . line
-      col_ = args ^. position . character
+      line_ = fromIntegral (args ^. position . line)
+      col_ = fromIntegral (args ^. position . character)
 
   expr <- loadFile uri_
   (welltyped, _) <- case typecheck expr of
@@ -395,8 +398,8 @@
       Right x -> return x
       Left msg -> throwE (Warning, Text.pack msg)
 
-  let _range = LSP.Types.Range (Position (unPos x1 - 1) (unPos y1 - 1))
-                      (Position (unPos x2 - 1) (unPos y2 - 1))
+  let _range = LSP.Types.Range (Position (fromIntegral (unPos x1 - 1)) (fromIntegral (unPos y1 - 1)))
+                      (Position (fromIntegral (unPos x2 - 1)) (fromIntegral (unPos y2 - 1)))
 
   let _newText= formatExpr chosenCharacterSet annotExpr
 
@@ -435,7 +438,7 @@
       Left _ -> throwE (Error, "Could not freeze import; failed to evaluate import.")
     assign importCache cache'
 
-    let _range = LSP.Types.Range (Position x1 y1) (Position x2 y2)
+    let _range = LSP.Types.Range (Position (fromIntegral x1) (fromIntegral y1)) (Position (fromIntegral x2) (fromIntegral y2))
     let _newText = " " <> hash
     return TextEdit{..}
 
@@ -457,8 +460,8 @@
 executeFreezeImport request = do
   args <- getCommandArguments request :: HandlerM TextDocumentPositionParams
   let uri_  = args ^. textDocument . uri
-  let line_ = args ^. position . line
-  let col_  = args ^. position . character
+  let line_ = fromIntegral (args ^. position . line)
+  let col_  = fromIntegral (args ^. position . character)
 
   txt <- readUri uri_
   expr <- case parse txt of
@@ -484,7 +487,7 @@
     Left _ -> throwE (Error, "Could not freeze import; failed to evaluate import.")
   assign importCache cache'
 
-  let _range = LSP.Types.Range (Position x1 y1) (Position x2 y2)
+  let _range = LSP.Types.Range (Position (fromIntegral x1) (fromIntegral y1)) (Position (fromIntegral x2) (fromIntegral y2))
   let _newText = " " <> hash
 
   let _edit = WorkspaceEdit
@@ -502,9 +505,9 @@
 completionHandler :: Handlers HandlerM
 completionHandler =
   LSP.requestHandler STextDocumentCompletion \request respond -> do
-    let uri_ = request ^. params . textDocument . uri
-        line_ = request ^. params . position . line
-        col_ = request ^. params . position . character
+    let uri_  = request ^. params . textDocument . uri
+        line_ = fromIntegral (request ^. params . position . line)
+        col_  = fromIntegral (request ^. params . position . character)
 
     txt <- readUri uri_
     let (completionLeadup, completionPrefix) = completionQueryAt txt (line_, col_)